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FS -- NIB Benelli M4 3 Position Receiver Extensions


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Hi all,


This is the same tube that is shipped with the 11707 and newer Benelli M4 models. The only reason you'd need to buy this item is if you have a M1014 or an 11703 model Benelli M4 that has the neutered receiver extension.


These receiver extensions are extremely difficult to get, and quantities are very limited. I actually have these receiver extensions in hand, so you won't have to play any waiting games. The parts inside the receiver extensions are brand new. I purchased them from Brownells myself.


There is a lot of misinformation concerning how to remove these recoil tubes from your weapon. Benelli will tell you that you will destroy the shotgun if you attempt to remove the extension. This is only true if you do not heat the threads to break the thread-locker.


Once you've developed the testicular fortitude to complete this project, you must do the following:


1. Clear the weapon of ammunition and make it safe.

2. Disassemble the weapon. Remove the barrel, bolt carrier group, trigger group and the stock.

3. A. Remove the internals from the receiver extension.

B. Use a pair of snap ring pliers to remove the snap ring at the bottom of the receiver extension.

C. Place a punch through one of the drainage holes to keep the spring from ejecting when you remove the plug.

D. Unscrew the spring retainer. I found the best tool for this job is the magnabit seen here:


The Weaver Clamp Screw, 080-430-625WB.

E. Contain the spring into the palm of your hand as the punch is removed.

F. Tip the receiver back to allow the plunger to slide out of the recoil tube. After that, you should spray the recoil tube out with solvent to remove oil and debris that might catch fire during the next process.


4. To remove the receiver extension, you must heat the receiver extension's lock-nut with a heat-gun for approximately 30 minutes or more. A propane torch would also work, and be faster. However, a heat-gun will be slower and safer. Benelli coats the threads with a green thread-locker compound. Make sure you put the receiver in a vice. I found the best place to clamp to was below the rear sight and upside down. You do not want to crush the receiver with the vice. Apply just enough tension to hold the receiver in place. Make sure you apply some padding between your receiver and the vice.


The nut is a 1 1/16" or metric equivalent box wrench. The nut is a common right-hand thread. Rightie Tightie, leftie loosey. It is best to used a closed box wrench to reduce the chance of slipping. Just slip it over the end of the receiver extension and seat it over the nut. You do not want to apply a lot of torque to the receiver. You want the heat to break the thread-locker's hold. I never used more than one arm to apply torque with. Once it is heated sufficiently, the nut will begin to turn slowly. Continue heating until the nut is completely removed and slides off the end of the receiver extension.


5. Now time for the hard part.

Note the depth that the receiver extension is screwed into the receiver. Look at the inside of the receiver to note the depth. Continue to apply heat to the receiver extension's threaded area. Use an open ended 3/4" box wrench on the flat spots of the receiver extension to apply torque. The Receiver Extension is also common right-hand thread. This may take another 30 minutes with a heat-gun to break the thread-locker compound's hold.


6. Once the receiver extension unscrews, clean up the threads of the receiver with acetone or another solvent. A wire-brush will help. If you want overkill, use Locktite primer on the threads of the receiver, the lock-nut and the new receiver extension.


7. To reassemble, I highly recommend that you apply red thread-locker to the receiver extension at this time. screw the new recoil tube in so that the threads are flush with the inside of the receiver. If you thread the receiver extension too far into the receiver, you will not be able to install the collapsible stock's pistol grip portion. The pistol grip threads onto the external threads of the receiver extension near the lock-nut. You'll notice that you can thread the receiver extension into the receiver all the way by hand. The only thing that really retains the receiver extension is the thread locker and the lock-nut. The receiver extension must be timed in order to correctly use the collapsible stock. If you have the collapsible stock, install the tail portion of the stock at this time and collapse it fully. Use the comb of the stock as an index point to align the receiver extension. The comb of the stock should point dead center to the rear iron sights. Once aligned, remove the stock. Thread the lock-nut over the receiver extension and tighten it. Re-check your alignment with the stock to make certain it is straight. I highly recommend applying red Locktite to lock-nut.


8. This extension for sale is complete, so you do not need to reinstall your internal parts into it.


9. Install your stock. Verify that it is aligning properly. Give the thread-locker 24 hours to cure before firing the weapon.


10. Reassemble the weapon. Perform a function test of the weapon to ensure that it is functioning properly.


Hopefully this tutorial is clear. This auction comes with the following brand new parts;

1. Benelli M4 3 Position Receiver extension (120)

2. Benelli M4 Main Spring (119)

3. Benelli M4 Stock Retaining Screw (45)

4. Benelli M4 Stock Retaining Ring (44)

5. Benelli M4 Flexible Ring (49 [Not Shown])

6. Benelli M4 Recoil Spring Plunger (46)


Naturally, I will assist anyone as much as I can with the disassembly/reassembly process.


PayPal users, please add 4% for the service fee. For users here, 200 dollars shipped each.



Edited by StrangerDanger
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